Various embodiments of the present invention are related to systems and methods for analog to digital data conversion, and more particularly to analog to digital converters with generalized beamformers.
Electronic signals most often take one of two forms, analog signals or digital signals. Analog signals can take any value between an upper and lower limit, smoothly changing values as the voltage or current is altered. Digital signals can take only a limited set of values, with the value being a number that represents a voltage or current level. Because the numbers are discrete, only a limited set of voltage or current levels can be represented by a digital signal. The granularity or resolution depends on the range of values represented and on the precision of the numbers representing the values in the digital signal.
An analog to digital converter (ADC) is an electronic circuit that converts analog to digital, typically by sampling the analog signal at regular intervals and producing a stream of digital values representing the voltage or current levels of the sampled analog signal. The sampling rate, the rate at which the analog signal is captured and converted to a digital value, should capture samples at twice the frequency of the highest frequency component in the analog signal, referred to as the Nyquist rate, or more.
A number of techniques have been developed to effectively increase the resolution of an analog to digital converter. For example, the resolution of an analog to digital converter may be effectively increased by oversampling and decimation, in which the sampling rate is greater than or equal to twice the Nyquist rate, and multiple samples are then added and averaged in a decimator or low pass filter to interpolate between sample values. However, for some applications, the output of an oversampling and decimating analog to digital converter is susceptible to distortion during downstream processing of the digital samples.
Thus, for at least the aforementioned reason, there exists a need in the art for increasing resolution and reducing distortion in an analog to digital converter.